package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Follow;
import com.hmdp.mapper.FollowMapper;
import com.hmdp.service.IFollowService;
import com.hmdp.service.IUserService;
import com.hmdp.utils.UserHolder;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.stream.Collectors;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    @Resource
    private IUserService userService;
    @Override
    public Result follow(Long followUserId, Boolean isFollow) {
        Long id = UserHolder.getUser().getId();
        if( isFollow){
            // 关注, 新增数据(当前用户)
             Follow follow = new Follow();
              follow.setUserId(id);
              follow.setFollowUserId(followUserId);
            boolean isSuccess = save(follow);
            if(isSuccess) {
                stringRedisTemplate.opsForSet().add("follow:" + id,followUserId.toString() );
            }
        }else {
            boolean isSuccess = remove(new QueryWrapper<Follow>()
                    .eq("user_id", id)
                    .eq("follow_user_id", followUserId));
            if (isSuccess) {
                stringRedisTemplate.opsForSet().remove("follow:" + id, followUserId.toString());
            }
        }
        return Result.ok();
    }

    @Override
    public Result followOrNot(Long followUserId) {
        Long id = UserHolder.getUser().getId();
         Integer count = query().eq("user_id", id).eq("follow_user_id", followUserId).count();
          return Result.ok(count > 0);
    }

    @Override
    public Result followCommon(Long id) {
        Long userId = UserHolder.getUser().getId();
        String key = "follows:" + userId;
        String key2 = "follows:" + id;
         Set<String> intersect = stringRedisTemplate.opsForSet().intersect(key, key2);
          if(intersect == null && intersect.isEmpty()) {
             return Result.ok(Collections.emptyList());
         }
           List<Long> ids = intersect.stream().map(Long::valueOf).collect(Collectors.toList());// 转换成Long
           List<UserDTO> users = userService.listByIds(ids).stream()
                    .map(user -> BeanUtil.copyProperties(user, UserDTO.class))
                   .collect(Collectors.toList());
        return Result.ok(users);
    }
}
